Wilhelmine von Grävenitz (1684–1744) was a German noblewoman, the favorite and royal mistress of Duke Eberhard Ludwig of Württemberg between 1706 and 1731.
The couple married in 1707, despite the fact that Eberhard thereby committed bigamy, being already married. From 1710, the couple lived in Ludwigsburg, while the wife of Eberhard Ludwig lived in Stuttgart. Grävenitz was politically active and was from 1717 until 1731 a full member of the secret government cabinet, which ruled the state. In 1731 the relationship was ended by Eberhard, and the year after, Grävenitz was given a pension and left Württemberg.